Bear spray is an aerosol in a metal canister. The active ingredient is capsaicin and capsaicinoids (1-2%). Think pepper-spray but larger and stronger. There is a nozzle that sprays the pressurized contents when the trigger is pressed down much like a fire extinguisher. The entire can is emptied in a high velocity stream in under 10 seconds. The fine cloud of spray temporarily reduces the bear’s sight, smell, and ability to breathe, allowing you leave the area safely.
Bear spray is proven highly effective in deterring bear attacks. As a non-lethal deterrent, bear spray protects you and your group from bear attacks. It has been shown to be 92% effective in deterring bear attacks. In fact, 98% of people carrying bear spray who got into close encounters with bears were uninjured. (Consequently, firearms are only 55% effective in deterring bear attacks.)
Bear spray should be carried anytime you travel in grizzly bear territory. In North America this includes Western Canada, Alaska, Montana, Idaho, and Wyoming. While engaging in activities such as hiking, fishing, biking, and camping, it should on your body and within reach at any given moment. A bear encounter is the worst time to fumble through your backpack in search of your bear spray, nor is it the time to learn about how to use it.